14 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [VOL. 10 



plus-minusve grannlari-scabridulis ; inflorescentiis pauciramosis ramis distichis, 

 bracteis primariis rigide erect is foliaceis 3-6 cm longis, aristatis vulgb 2 flores 

 subtendentibus, flore altero cum prophyllo subtendenti, bracteis sueeessivis (2-5) 

 gradate parvioribus, quoque vulgo flores duos subtendenti. ultima vulgo flores 

 tres subtendenti; pedicellis compressis 3-angulatis 15-30 mm longis; sepalis 3, 

 lanceolatis acutissimis involuto-conduplicatis, scario-marginatis, 5-7 mm longis, 

 ea. 1.5 mm latis. conduplicatis, imbricatis, duobus posterioribus subappositis, 

 valde erectis, ca. 7 mm longis, anteriori deflexo (in anthesi) ca. 5 mm longo; 

 petalis 3. flavidis, rhomboideo-ovatis, ea. 10 mm longis, ca. 6 mm latis, obtusis, 

 ad basim late sessilibus, plus-minusve 20-flabellinervis ; staminibus 3, petalis 

 appositis, 5.0-5.5 mm longis, filamentis 3.5-4.0 mm longis. ad basim tumidis, 

 antheris versatilibus evidenter extrorsis, 2.0-2.5 mm Longis, sagittatis, in maturi- 

 tate 2-theeatis, lobis ba.silaribus obtusis 0.7-0.8 mm longis. apiee emarginato; 

 granis pollinis sphaeroideis non-aperturatis, 32-34 /x diam., sporodermis sub- 

 tesselatis (ad X 830 mag.) ; ovario trigonali 3-loculari. placentis axialibus in 

 quoque loculo 2-seriatis. stylo simplici. stigmatc minute 3-lobato ; seminibus 

 sphaeroideo-ovatis. minute biapiculatis. minute iongitudine longistriatis, 1.5- 

 2.0 mm longis. 



VENEZUELA: Amazonas: Cerro de la Neblina, approach to southeast escarpment, upper 

 Canon Grande Basin, alt. 2000 m ; perennial herb with horizontal rootstock and strongly 

 distichous leaves; flowers yellow; common in low Bonnetia-Tyleria scrub bush; 14 Dec 1957, 

 B. Maguire, J. J. Wurdach 4r C. K. Maguire 42402 (holotype NY) ; near east escarpment of 

 upper Canon Grande Basin, alt. 2000 m; perennial herb with yellow flowers; Maguire, Wur- 

 dach 4' Maguire 42386 (paratype). 



The monotypic genus Achlyphila is known only from the upper basin of 

 Canon Grande on Cerro Neblina, where it is locally common as an understory 

 plant in low Bonnetia-Tyleria. scrub woodland. There on the southeast cumbre 

 at 2000 m altitude the landscape is almost constantly bathed in clouds that pour 

 over the eastern escarpment and flow down across the basin. The name Achly- 

 phila indicates this environment. 



2. Xyris Linnaeus, Sp. PI. 42. 1753. 



With more than 250 species, Xyris is taxonomieally the most complex and 

 geographically the most widespread genus of the family. The largest concentra- 

 tion of species and probably the chief centers of distribution of Xyris occur in 

 tropical America. The genus is prominently represented in marshy or wet areas 

 in Xorth America, Africa, Asia, and Australia, but is lacking in Europe. 



Xyris has been divided taxonomieally into three sections, viz., sect. Poma- 

 toxyris Endlicher (Gen. PI. 124. 1841)" characterized chiefly by a basally 3- 

 locular capsule, with perhaps fewer than twenty species confined to Australia; 

 sect. Euxyris, characterized by a unilocular capsule and parietal placentation. 

 of possibly more than one hundred pantropical and North American species; 

 and sect. Nematopus Scubert (Fl. Bras. 3 1 : 211. 1855). in which the capsule is 

 likewise unilocular, but the placentation basal, of probably more than one hun- 

 dred species confined to tropical America. 



3. Orectanthe Maguire. Mem. X. Y. Bot. Gard. 10: 2. 1958. 



The Two species are known only from South American Guayana, and there 

 are confined to higher elevations on Roraima sediments. 



